SRM Dilution Calculations

My prior calculations were incorrect!

As I mentioned previously, Laura and I need to run dilutions of our samples to confirm that as the concentration of protein in our samples decreases, the assay does not detect them as intensely. When I showed Emma my calculations, she suggested making dilutions based on protein concentrations (µg) as opposed to µL of sample added. Here are my final numbers:

Table 1. Dilution calculations

Vial

Dilution Ratio

µg to Inject

µL to Inject

µg oyster Needed

µg geoduck Needed

µL oyster needed ((µg/µL)x15 µL/1 µg/µL)

µL geoduck needed ((µg/µL)x15 µL/2 µg/µL)

PRTC added

µL ACN

Total Volume (µL)

1

10:1

1

1

0.9

0.1

13.5

0.75

1.5

N/A

15.75

2

7.5:1

1

2

0.87

0.13

6.5

0.5

0.75

7.25

15

3

5:1

1

2

0.8

0.2

6

0.75

0.75

7.5

15

4

2.5:1

1

2

0.6

0.4

4.5

1.5

0.75

8.25

15

5

1:2.5

1

2

0.4

0.6

3

2.25

0.75

9

15

6

1:5

1

2

0.2

0.8

1.5

3

0.75

9.75

15

7

1:7.5

1

2

0.13

0.87

1

3.25

0.75

10

15

8

1:10

1

1

0.1

0.9

1.5

6.75

1.5

5.25

15

For PRTC, our stock concentration volume is 0.5 pmol/µL. I changed the injection volume for the 10:1 and 1:10 dilutions from 2 µL to 1 µL to ensure we were pipetting volumes over 0.5 µL. This made it so that the final volume for the 10:1 injection was 15.75 µL, but Emma said that was okay.